Printable logic circuits comprising self-assembled protein complexes.

Area of Science:

• Molecular electronics
• Biomolecular engineering
• Nanotechnology

Background:

• Traditional digital logic circuits rely on semiconductor materials.
• Molecular electronics aims to use individual molecules or molecular assemblies to create electronic components.
• Self-assembly is a key process in biological systems and a promising strategy for bottom-up fabrication.

Purpose of the Study:

• To fabricate digital logic circuits using protein complexes.
• To investigate the electrical properties of protein-based resistors and diodes.
• To demonstrate the functionality of all-protein logic gates and circuits.

Main Methods:

• Fabrication of protein complex-based resistors and diodes.
• Wiring components using printed liquid metal electrodes.
• Inducing self-assembly of protein complexes into anisotropic and isotropic monolayers.
• Characterizing charge transport properties and electrical conductivity.
• Constructing and testing AND and OR logic gates and pulse modulators.

Main Results:

• Protein complexes formed functional resistors and diodes with temperature-independent charge transport.
• Self-assembly into anisotropic monolayers created directional conductivity.
• Self-assembly into isotropic monolayers resulted in non-directional conductivity.
• All-protein logic gates (AND, OR) and pulse modulators demonstrated robust functionality, closely matching simulations.

Conclusions:

• Digital logic circuits with useful functionality can be constructed from readily available biomolecules.
• Molecular self-assembly is a viable technique for fabricating molecular electronic devices.
• This work advances the field of molecular electronics by realizing functional protein-based logic circuits.